Calcified frontal subperiosteal hematoma with a bone-on-bone appearance: a rare head injury complication in an adult.

Background: Subperiosteal hematoma is predominantly described in neonates, where it usually results from birth trauma. While most cases resolve spontaneously, a few may progress to calcification. Adult cases are uncommon, particularly those presenting several years after the initial trauma. The condition may pose a diagnostic challenge and can mimic other bony scalp swellings. Detailed clinical evaluation and characteristic radiological features are crucial for diagnosis
Case presentation: We present a 25-year-old man with a painless frontal bony scalp swelling, six years after he sustained a traumatic frontal subperiosteal hematoma. Computed tomography scan showed a frontal bone-on-bone appearance at the site of the previous subperiosteal hematoma, suggesting calcification of the hematoma. He declined surgical excision and he is being followed-up.
Conclusion: This case highlights a rare delayed presentation of calcified frontal subperiosteal hematoma in an adult. It emphasizes the importance of detailed medical history and consideration of calcified subperiosteal hematoma among the differential diagnoses of bony scalp swellings. Recognition of its distinctive imaging features is essential for diagnosis.

Bone-on-bone appearance calcified frontal bone head injury subperiosteal hematoma.